Optical coupling device, method of producing the same, and optical apparatus using the same

Abstract

An optical coupling device, a method of producing the same, and an optical apparatus using the same. A light transmitting medium of the optical coupling device is made of optical fibers to transmit the light. Three RGB laser beams can be compounded by forming one output end after heating one end of the optical fibers. Input ends of the optical fibers each have a lens to collimate each laser beam. A collimating lens installed at an output end of the optical fibers changes the compounded laser beam to a parallel ray. The optical coupling device made of the optical fibers can be applied to an image reproducing apparatus such as a projector and a projection TV. Especially, when the optical coupling device using the optical fibers is applied to an image reproducing apparatus having a DMD (digital micro-mirror device), the size of the image reproducing apparatus can be reduced and the quality of the image reproduced is improved.

1 . An optical coupling device comprising: 
 a light transmitting medium having a plurality of input ends and one output end;    a first lens installed at each of the input ends of the light transmitting medium to collimate an input light; and    a second lens installed at the output end of the light transmitting medium to transmit the input light and to compound the input light into one parallel ray.    
   
   
       2 . The optical coupling device of  claim 1 , wherein the light transmitting medium is an optical fiber.  
   
   
       3 . The optical coupling device of  claim 1 , wherein the second lens is a collimating lens.  
   
   
       4 . A method of producing an optical coupling device comprising the steps of: 
 forming one output end by heating an end of a plurality of optical fibers; and    connecting a first lens with an input end of the optical fibers and a second lens with the output end.    
   
   
       5 . The method of producing the optical coupling device of  claim 4 , wherein the step of forming the output end includes the steps of: 
 bounding a point placed at a certain distance from the input end of the plurality of optical fibers and heating; and    extending the heated one end of the optical fibers.    
   
   
       6 . The method of producing the optical coupling device of  claim 5 , wherein the step of forming the output end further includes the step of polishing the output end.  
   
   
       7 . The method of producing the optical coupling device of  claim 4 , wherein the second lens is a collimating lens.  
   
   
       8 . An optical apparatus using an optical coupling device, comprising: 
 a light generation unit to output a light;    a light composition unit made of a plurality of optical fibers, the light composition unit being operative to compound the light input from the light generation unit; and    a light scanning unit to form an image by projecting the compounded laser beam onto a screen.    
   
   
       9 . The optical apparatus using an optical coupling device of  claim 8 , wherein the light generation unit includes: 
 a light source to release the laser beam;    a light separation unit to separate the released laser beam into monochromatic lights having different wavelengths; and    a light modulation unit to modulate the separated monochromatic lights according to each wavelength.    
   
   
       10 . The optical apparatus using an optical coupling device of  claim 8 , wherein the light composition unit includes: 
 a light transmitting medium having a plurality of input ends and one output end;    a first lens installed at each of the input ends of the light transmitting medium to collimate an input light; and    a second lens installed at the output end of the light transmitting medium to transmit the input light and to compound the input light into one parallel ray.    
   
   
       11 . The optical apparatus using an optical coupling device of  claim 10 , wherein the second lens is a collimating lens.  
   
   
       12 . The optical apparatus using an optical coupling device of  claim 8 , wherein the light scanning unit scans the monochromatic lights onto a screen vertically and horizontally.  
   
   
       13 - 17 . (canceled)